Knitting machine yarn carrier bar control



Oct. 29. 1940. T M

KNITTING MACHINE YARN CARRIER BAR CONTROL Filed April 15. 1958 16Sheets-Sheet l FI.E-J.-

IN V ENTOR.

ATTORNE;

Oct. 29, 1940. F, UTEM 2 219 733 E YARN CARRIER BAR CONTROL 165Sheets-Sheet 2 KNITTING MACHlN Filed April 15, 1958 Fla--5- INVENTORI 4FredAwI/z'm ATTOR Y.

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l6 Sheets-Sheet 6 Oct. 29. 1940.

KNITTING MACHINE YARN CARRIER BAR CONT Filed April 13, 1938 i I I 1 2 i5 as w INVENTORI Fred Juiem,

ATTORNEY.

0a. 29. 1940. F. AUTEM 2,219,733

KNITTING MACHINE YARN CARRIER BAR CONTROL Filed April 13, 1938 16Sheets-Sheet 7 31 gm 1 .L 13-- ll. 52 fiqz INVENTORI 90 Fredflui'em,

O t, 29, 1940. F. AUTEM 219 733 KNITTING MACHlNE YARN CARRIER BARCONTROL Filed April 13, 1958 16 Sheets-Sheet 8 is [I E -15. 15 I 50.9 Iv Q) V 1 dflfNVgNmR:

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ATTORN OCt- 29, 1940. F' AUTEM KNITTING MACHINE YARN CARRIER BAR CONTROLFiled April 13, 1958 16 Sheets-Sheet 1 O Frdlwifem,

0a. 29, 1940. AUTEM 2,219,733

' KNITTING MACHINE YARN CARRIER BAR CONTROL Filed April 15, 1958 16Sheets-Sheet ll FLE-JET V 939% 2 IN'VENTDK' Fn d Au em,

BY I I AmRNEK Oct. 29, 1940.

F. AUTEM KNITTING MACH'LNE YARN CARRIER BAR CONTROL Filed April 15, 195816Sheets-Sheet 12 IN VEN TOR. Fred Hui 72m,

'Oct. 29, 1940. AUTEM KNITTING MACHINE YARN CARRIER BAR CONTROL FiledApril 13, 1938 16 Sheets-Sheet l3 Fi s-.55.

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ATTORNEY;

Oct. 29, 1940. I AUTEM 1 2327197733 KNITTING MAcHiNE YARN CARRIER BARCONTROL Filed April 15, 1958 16 Sheets-Shej; 15

INVEN Fred flwi em,

I l I 1% ATTORNEY.

Oct. 29, 1940. F. AUTEM 2,219,733

- KNITTINQ MACHINE YARN CARRIER BAR CONTROL I Filed April 15; 1958 16Sheets-Sheet l6 F1. r3- 3E:

INVENmR: Fred Am? m,

BY I

' ATTORNEY.

Patented Oct. 29, 1940 UNITED STATES PATENT OFFICE KNITTING MACHINE YARNCARRIER. BAR

CONTROL Fred Autem, Wyomissing, Pa., assignor to Textile Machine Works,Wyomissing, Pa, a corporation of Pennsylvania This invention relates tothe actuation and control of yarn carrier mechanisms for knittingmachines capable of operation in recurrent sequence and otherwise, andparticularly to means a for automatically operating the yarn selectormechanisms and friction boxes in full fashioned knitting machines.

In full fashioned knitting machines, mechanisms have been developed forlaying yarns of the 30 same color and kind, but brought from differentcones or supplies, in recurrent sequence, such as the now well knownthree-carrier attachments, whereby three yarns, instead of one, are laidin repeated succession to avoid rings or shadows.

This principle, operating on a' law of averages, depends for its resultson the unlikelihood of lengths of any one of the three yarns ofirregular diameter being laid immediately next to similar lengths ineither of the other two yarns; these lengths being of irregular diameteroccurring occasionally along silk threads.

The multi-carrier fabric has been produced by mechanism whereby thecarrier operation is effected automatically, but wherein the operationsfor rendering the mechanism active and inactive were manually efiected.Means also has been devised whereby a single friction box carrying oneof the aforementioned three-carrier selectors may be manually orautomatically changed from its 80 three-carrier operation to theoperation of a single carrier of the sequence. Thus, a three-carrierattachment, operating through full strokes in the leg area of a stockingblank, could be manipulated to lay one of the three yarns through 85short strokes, as in the reinforced heel area of a stocking.

These devices are of various designs, but they each require a specialand relatively heavy, friction box which, although in certain cases itwould be better to avoid its use as an actuating means for effecting thelaying of single short course yarns, is, and has been, generally used assuch, because of the desirability, in certain instances, of convenientlyestablishing an operative connection with as many carriers as possible.

The use of the above-mentioned special threecarrier friction boxes foroperating the three carriers in sequence, and one of the three carriersalone, has been general, but no means, so far as I am aware, has everbeen suggested for automatically throwing the three-carrier selectorinto and out of operation, for automatically connecting the special boxto, and releasing it from, the friction rod, for operating a singlecarrier other 55 than one of the sequential carriers, or for combiningsuch operations with other operations, such as the .aforementionedoperation of automatically changing the device back and forth betweenthe sequential, or three-carrier operation, and other carrier operationsuch as the single- 5 carrier operation mentioned. The operation of sucha comparatively large and heavy special friction box, in the shortstroke single yarn areas of the heel of a stocking blank, generateslarger amounts of heat and wear, from the greater I0 movements of thefriction rod through the box at the ends of the short strokes, comparedto the heat and wear of a smaller standard single carrier box.

It is an object of this invention to increase the flexibility, andchoice, of control over the yarn carriers and friction boxes of fullfashioned knitting machines, whereby to enable such machines not only tobe operated as fully and effectively as they have ever heretofore beenoperated, but also 20 to provide added features materially enhancing thedesirability and usefulness thereof.

Another object of the invention is to provide a feature whereby, incertain instances of highspeed production, the three-carrier or special26 friction box of a full fashioned knitting machine may be rested, orrelieved of heating and wear, during the knitting of areas, such as theheel tabs of a leg blank.

Another object of the invention is to provide a 30 multiple-carrierattachment which may be auto matically controlled as above set forth,between totally inactive condition and sequential-carrier operation.

Another object of the invention is to provide an attachment of theabove-indicated character which may be automatically operated betweensequential-carrier operation and other carrier operation, such as theoperation of a single carrier of the sequence, or a carrier not of thesequence. 40

A further object of the invention is to provide an attachment of theabove-indicated character which may automatically control a combinationor sequence of the above-mentioned actions, and be operated incooperation with the automatic (5 operation of the friction box, betweenactive and inactive positions.

With these and other objects in view, which will become apparent fromthe following detailed description of the illustrative embodiments ofthe invention shown in the accompanying drawings, the invention residesin the novel elements, features of construction and arrangement of partsin cooperative relationship, as hereinafter more particularly pointedout in the claims.

In the drawings:

Figure 1 is a top plan view, parts being omitted and intermediatesections being broken away to shorten the figure, of a multi-sectionstraight knitting machine embodying the invention, and adapted toproduce full fashioned stocking blanks;

Fig. 2 is a view taken cross sectionally of the machine of Fig. 1,slightly enlarged thereover;

Fig. 3 is a further enlarged detail view of a three-carrier attachmentand other parts as viewed generally in the direction of an arrow C ofFig. 2, certain parts being in elevation, others in section, and othersbeing broken away or omitted;

Fig. 4 is an enlarged detail view of parts of the structure of Fig. 3,as viewed in the direction of an arrow D in Fig. 2;

Fig. 5 is a sectional view taken substantially along the line 5-5 ofFig. 4;

Fig. 6 is a sectional view taken substantially along the line 6-6 ofFig. 3;

Fig. 7 is a sectional view taken substantially along the line 1-1 ofFig. 3;

Fig. 8 is a detail view, on a reduced scale, of certain parts as seennear the upper part of Fig.

Fig. 9 is a sectional detail view taken substantially along the line 9-9of Fig. 7;

Fig. 10 is a sectional view taken substantially along the line Ill-l0 ofFig. 7;

Fig. 11 is a view similar to the view of Fig. 7, with the parts thereofshown in different positions;

Fig. 12 is a sectional view taken substantially along the line l2-i2 ofFig. 1;

Fig. 13 is a sectional view taken substantially along the line l3-l3 ofFig.12;

Fig. 14 is a detail view, in section, taken substantially along the line[4-H of Fig. 11;

Fig. 15 is a sectional view taken substantially along the line l5-l5 ofFig. 3;

Fig. 16 is a view of certain of the parts shown at the upper portion ofFig. 15, but in different positions; I

Fig. 17 is a sectional view taken substantially along the line I'l-l'lof Fig. 15;

Fig. 18 is a detail view, cross sectionally of a control shaft of themachine, showing certain cams on the shaft and followers for the cams;

Fig, 19 isa cross sectional view taken substantially along the linel9-l9 of Fig. 3;

' Fig. 20 is similar to Fig. 19, showing the parts thereof in differentpositions;

Fig. 21 is a sectional view taken substantially along the line 2l-2l ofFig. 19;

Fig. 22 is a view taken substantially along the the line 22-22 of Fig.3;

Fig. 23 is a sectional view taken substantially along the line 23-23 ofFig. 22;

Fig. 24 shows parts as viewed generally in the direction of an arrow Fof Fig. 6;

Fig. 25 is a view taken substantially along the line 25-25 of Fig. '7; a

Fig. 26 is a view taken substantially along the line 26-25 of Fig. 3;

Fig. 27 is a, sectional view taken substantially along the line 21-21 ofFig. 3;

Fig. 28 is a sectional view taken substantially along the line 28-28 ofFig. 6;

Fig. 29 is a diagram of the leg blank of a full fashioned stocking,together with pattern chains, as developed or opened out along straightlines in side elevation from the normal closed loop shape thereof,indicating the positions along the blank at which certain operations areeffected by the chain links;

Figs. 30, 31, 32, 33, 34 and 35 are a progression of diagrammatic viewsillustrating the manner in which three carrier rods are operated inrecurrent sequence to produce knitted areas of the ringless type;

Fig. 36 is a view similar to one of Figs. 30-35 showing how only onecarrier rod is operated by the three-carrier attachment at certaintimes, as in laying the yarn of the stocking welt;

Fig. 37 is a view of parts of a modified form of the inventioncorresponding to the structure of Fig. 3; and

Fig. 38 is a view corresponding to Fig. 6, of the modified form of theinvention of Fig. 37.

In the drawings and description, only those parts necessary to acomplete understanding of the invention have been set forth; furtherinformation as to the construction and operation of other elements notherein specifically pointed out, but which are usual and well known,being available in the pamphlet entitled Full Fashioned KnittingMachines, copyright 1920, in the Reading Full Fashioned Knitting MachineCatalogues, copyright 1929 and 1935, published by the Textile MachineWorks, Reading, Penna, and in a pamphlet entitled Knitting MachineLectures, published in 1935 by the Wyomissing Polytechnic Institute,Wyomissing, Pennsylvania.

Reference may also be had to Patent No. 2,101,048 entitled Uninterruptedknitting of shaped fabrics, and issued December 7, 1937, to Alfred E.Ischinger.

Machine ,frame The machine frame comprises transverse end and centerframes, and longitudinal members mounted on these frames, such as afront beam, a back beam, a front bed and a center bed; these parts beingsimilar to corresponding members heretofore employed in full fashionedstocking and other straight knitting machines, except as modified as tobearings and other supporting partsfor the operating mechanisms whichare new to this invention.

Referring to the drawings, the machine of Figs. 1-36 is of themulti-section type comprising, as better seen in Figs. 1 and 2,transverse end frames l2, and transverse center frames l3, joined by afront beam H, a back beam I1, and a center bed I8, which cooperate witha front bed l9 extending only between the center frames l3 to form abase upon which the operating parts of the machine are supported.Between each pair of the center frames Hi, there is a knitting mechanismfor simultaneously knitting two stocking blanks.

M ain drive mechanism A power unit for driving the operating parts ofthe machine, shown in the above-mentioned catalogues, is also similar tothe power units of previous machines of the type producing fashionedknitted fabrics, including an electric motor on the machine frame at therear of the machine, connected through sprocket wheels and a chain to ahand wheel shaft and, through a clutch and further sprocket wheels and achain to a drive shaft, from which a coulier motion mechanism derivesits motion. This power unit drives, in this instance, a cam shaft 22, afriction rod 23 and a slurcock box connecting rod 24.

Loop forming mechanism In knitting a fabric, such as a full fashionedstocking blank, after the yarns are laid in lengths ready for forminginto loops, the usual loop forming parts, such as needles, sinkers,dividers and knockover bits, which are the parts directly engaging theyarn, are operated similarly to the manner in which such parts haveheretofore been operated.

Loop forming mechanism (Figs. 2 and 4) comprises needles 32, two banksor sets of which are disposed between each pair of adjacent centerframes I3. The needles of each bank are held, by clamps 33, to a needlebar 34. which is pivotally connected by a bracket 81 fixed thereto, anda pin 38, to a lifting arm 39 on a needle bar lifting shaft 42, on whichis also mounted an arm 43 carrying a follower roller 44 on a shaft 41.The arm is connected, by a spring 48, to a bracket 49 on the back beamI1. The follower 44 cooperates with cams, including a cam 52. on the camshaft 22.

Forward and rearward movements of the needles are eifected by a fork 53fixed to the needle bar 34, and pivotally connected to a lever 54 havinga notch 51 for resting thelever 54 on a 7 pin 58 projecting from theside of a presser lever 59. The latter is carried by a presser shaft 62,

and carries a follower roller 83 for cooperation with cams, including acam 81, on the cam shaft 22. The presser lever 59 is connected, by aspring 12, to a bracket 18 on the back beam I1 for biasing the follower63 toward its cam.

By lifting the lever 54 to remove the notch 51 from the pin 58, theneedles may be moved from the operative position shown to an inoperativeposition in which a notch 14 is placed over the pin 58, and which is aposition of the needles forward of the sinkers and dividers, for repairwork, such as the replacement of needles. The lever 54 also has ashoulder 11 for cooperation with the pin 58 to hold the needle bar in anintermediate position.

A sinker head assembly comprises a sinker head 82, sinkers 83 anddividers 84 which are thin sheet steel elements disposed alternately inclose sideby-side relation, and a verge plate or stop 81 for thesinkers.

The sinkers 83 are moved forwardly by jacks 88 which are slurredforwardly by a slur cam 89 secured to a cock box 92 mounted on a guiderail 93 for slidable movement transversely to the sinkers and dividers.The cock box 92 is secured to the connecting bar 24 and is reciprocated,

parallel to the front of the machine, by the coulier motion mechanism ina usual manner.

The dividers 84 are moved forwardly and backwardly by a catch bar 94,which receives its movement from cams including a cam 91 on the camshaft 22, through a linkage comprising a cam follower 98, a back catchlever 99, and a vertical shifting lever I02 mounted on a. shaft I03, anda horizontal lever I04. A spring I05, connected between a hook extensionI06 of the lever 99 and a bracket arm IIO on the front beam I4, biasesthe follower 98 against the cam 91.

The sinkers 83 are engaged and disengaged by the catch bar 94, by meansof a front catch bar linkage comprising cams, including a cam I01, onthe cam shaft 22, a. cam follower I08, a front catch lever I09, and alink II 2 secured to a front catch shaft II3, a vertical lever H4, and ahorizontal link I I1.

As the yarn is laid to the needles 32, the sinkers 83 are slurredforwardly by the jacks 88 and .the slur cam 89, in spaced relation tothe yarn carriers, to sink the yarn between alternate pairs of sinkers.

needles. The dividers 84 are then brought forward by the catch bar 94and its back cam linkage to complete the formation of the loops in theusual manner. Retracti'on, and further advancement of the sinkers 83with the dividers 84 are accomplished by the catch bar 94, which islowered by the front catch bar cam I01, and associated cam linkage. toengage the backs of the Knockover bits II8 cooperate with the sinkers,dividers and needles to hold several adjacent previously knitted coursesin position while the needles are pulling the loops of a new coursethrough the loops of the last previous course.

Yarn laying means As is usual in a straight knitting machine, yarn isdrawn from supply packages or cones, at the rear of the machine, andmoved by feeding mechanism to a yarn laying means at the front of themachine, whereby the yarn is fed to the knitting head for formation intoloops.

Yarn laying means comprises carrier rods I-8, inclusive, at the front ofthe machine, parallel, and adjacent to, the friction rod 23, andlongitudinally reciprocably mounted in brackets I20 on the center bedI8. Yarn carriers, or guide fingers similar to guide fingers I2I, I22and I24 on M ain pattern unit Pattern mechanism, by which the sequenceof operation of various movable elements of the machine is controlled,comprises in this instance, a usual pattern chain at the front of themachine, known as a main pattern unit, because it is the primary sourceof pattern control, and because there is another pattern unit auxiliaryto, and controlled by, the main pattern unit.

A main pattern unit M (Fig. 1) comprises a bracket I21 on the front beamI4, a shaft I28 journaled in the bracket I21, a sprocket wheel or drumdevice I29 on the shaft I28, and a double chain element I32, acting asone chain, on the sprocket wheel I29. The chain I32 is supported alongthe front of the machine, on idler rollers (not shown).

The chain is advanced about the sprocket wheels by a ratchet wheel I33,which is operated by a pawl pivotally mounted on the bracket I21 andintermittently actuated by a lever I31 carrying a follower forcooperation with a cam on the'cam shaft 22.

A stub shaft I42 is supported in the bracket I21, transversely to thecam shaft 22, and carries a follower I43 disposed between shogging camsI41 and I48 on the cam shaft 22.

A member I49 is fixed at one end to the stub shaft I42, and is slidablysupported parallel to the shaft on the bracket I21. A tension spring IE2is connected between the slide member I49 and the stationary bracket I21, and tends to move the stub shaft I42 whereby to move the follower I43 from its normal knitting position, between the shogging cams I41 andI48, to its narrowing position, also between the cams I41 and I48, whereit engages other face cam portions of the cams to shoe: the cam shaft22. The spring I82 is normally prevented from moving the stub shaft by alatch I83, which is released by a button on the chain I32. The stubshaft I42, and the follower I43 thereon, are returned to latchedinactive position, against the action of the spring I82, by cooperationbetween a cam I 54 on the cam shaft 22, and a follower I51 on the slidemember I48.

A handle lever I58 is pivotally mounted on a shaft I58, and carries apawl which, by oscillating the handle engages the ratchet wheel I33 tomanually advance the chain I32 independently of its power advance whendesired. This handle also carries a lever which, when the handle isturned about the shaft I59 to effect the manual adjustment of the chain,is advanced to position which will prevent shogging of the cam shaft 22,by preventing movement of the stub shaft I42 and the follower I43 frominactive to active position if, at this time, a button on the chain I32should release the latch I53 ordinarily permitting the stub shaft toadvance by action of the spring I62.

A plurality of levers G of the main pattern unit M are disposed inside-by-side relation, severally for operation by a button or buttons.I62 on the chain I32. Rods R (Fig. 2), including a rod I63 which is theonly one thereof necessary to an understanding of the invention, arelongitudinally slidably mounted along the front of the machine inbracket bearings secured to the front beam I4. The rods R operate tocontrol various mechanisms of the machine; the rod I63 being actuated bya lever I64 of the levers G to control the operation of an auxiliarypattern unit A (Figs. 1, 2, 6, '7, 11 and 27).

Auzilary pattern unit To simplify the construction and operation of themain pattern unit M above set forth, and also to simplify the machinegenerally and to render it more convenient to control any of variousmechanisms from control means closer thereto, the auxiliary control unitA is provided along the rear of the machine. It is operated from the camshaft 22 and controlled by the main pattern unit M to operate, in asmaller number of steps than the steps or operations of the main patternunit, which are provided one for each course or partial course formed inthe blank being knitted.

The rod I63, above set forth, has fixed thereto a pair of closelyadjacent collars I61, spaced a slight distance apart along the rod,between which collars is disposed the lower end of a vertical arm (Fig.2) of a lever I68. The latter has a horizontal portion, pivotallymounted by a vertical pin I68 on the top of the front beam I4, and ahorizontal latch arm portion I12 for movement, when the rod I63 isshifted longitudinally, laterally to a lever I13, between a positiondirectly under an arm I14 of the lever I13 and a position aside the armI14.

The lever I13 is pivotally mounted on a narrowing lift shaft I11, andhas an upright arm I18 carrying a roller or follower I18 for cooperationwith a cam I82 on the cam shaft 22. A link I 83 is pivotally connected,at one end, to the upper end of the arm I18, and at its other end, to amember I84 that is relatively movably mounted on a control or timingshaft I81 of the auxiliary pattern control unit A at the rear of themachine. The shaft I81 extends substantially throughout the length ofthe machine, and is journaled in bearing brackets I88 fixed to a bar I88of rectangular cross section that is mounted on the end and centerframes I2 and I3, respectively.

The member I84 pivotally carries a pawl I82 for advancing a ratchetwheel I83 fixed to the shaft I 81. An idler pawl I84, pivoted on a pinI81 carried by one of the bearing brackets I88, is held by a spring I88against the ratchet wheel I83 to prevent reverse rotation of the latter.A third pawl I88 (Fig. 1), also pivoted on the pin I81, but cooperatingwith a second ratchet wheel 282, reverse to the ratchet wheel I83 andfixed to the latter, normally tends to prevent advancement of the firstratchet wheel I83. Thus, with the idler pawl I84 locking the ratchetwheel I83 against reverse movement, and the pawl I88 locking the ratchetwheel 282 against forward movement, the shaft I81 is positively lockedagainst accidental movement in either direction, from vibration or othercause, and cannot be operated, except when the link I83 is operated bythe cam I82, and then only in the forward direction. When this occurs,an arm 283, on the pawl I82, first cooperates with a pin 284 on the pawlI88 to move the latter, against the action of a spring (not shown), torelease the ratchet wheel 282 so that, upon continued movement of thepawl I82, the ratchet wheel I83, and consequently, the shaft I81 areadvanced by a distance of one notch of the ratchet wheel I83.

The cam I82 is generally of true circular form with the exception of aflat portion 281. Tile arm I14 of the bell crank I13, is latched by thearm I12, to hold the follower I18 at the high point, or circular part,of the cam I82. A tension spring 208', extending between an extension208 of the link I83 and a bracket 2I2 on the back beam I1, biases thefollower I18 toward the cam I82, and the arm I14 toward the latch armI12, so that, when the latch arm is under the arm I14, the force of thespring 288 is exerted against the latch arm I12, and the follower I18 isprevented from following the contour of the cam I82. When the latch armH2 is moved laterally from under the arm I14, the force of the spring288 causes the follower I18 to follow the contour of the cam I82, eachrevolution of the cam thereby advancing the ratchet wheel I83 one notch.

Along the auxiliary control shaft I81, on sprocket wheels 2I3 fixedthereto adjacent to corresponding sub-mechanisms of the machinecontrolled thereby, are pattern means in the form of variable linkcamming chains, including chains 2I6, 2I1, 2I8 and 2I8 to be driven bythe shaft I81 through the sprocket wheels 2I3. The chain 2I8 is the onlyone of the chains 2I6-2I8 having links of more than two heights, theselinks being, as better seen in Fig. 29, high links 224, links 225 ofintermediate height, and low links 226. The chain 2I8 has high links 228and low links 22I; the chain 2" has high links 2" and low links 2I5; andthe chain 218 has high links and low links. Sectional or other cam discsmay be substituted for the sprocket wheels 2I3 and the chains, or acombination of chains and discs employed for diiferent mechanisms.

Each of the sprocket wheels 2I3 and idler sprocket wheels (not shown),which assist in supporting the camming chains, is provided withperipherally spaced transverse grooves 222 for receiving pins 223connecting the links of the chains 2I6-2I8. The periphery of each chainis acam or pattern device for cooperation with an element or follower,in which the cam device provides for selective variations in itscapacity, and 7

